In November 2015, Saúl Luciano Lliuya, a Peruvian farmer who lives in Huaraz, Peru, filed claims for declaratory judgment and damages in a German court against RWE, Germany’s largest electricity producer. Lliuya’s suit alleged that RWE, having knowingly contributed to climate change by emitting substantial volumes of greenhouse gases (GHGs), bore some measure of responsibility for the melting of mountain glaciers near his town of Huaraz, population 120,000. That melting has given rise to an acute threat: Palcacocha, a glacial lake located above Huaraz, has experienced a substantial volumetric increase since 1975, which has accelerated since 2003. Lliuya presented several legal theories in support of his claim, including one that characterized RWE’s emissions as a nuisance that Lliuya had incurred compensable costs to mitigate. Acknowledging that RWE was only a contributor to the emissions responsible for climate change and thus for the lake’s growth, Lliuya asked the court to order RWE to reimburse him for a portion of the costs he and the Huaraz authorities had incurred to establish flood protections. That portion was 0.47% of the total cost — the same percentage as Lliuya’s estimate of RWE’s annual contribution to global greenhouse gas emissions.
The court dismissed Lliuya’s requests for declaratory and injunctive relief, as well as his request for damages. The court noted that it could not provide Lliuya with effective redress (Lliuya’s situation would not change, the court said, even if RWE ceased emitting), and that no “linear causal chain” could be discerned amid the complex components of the causal relationship between particular greenhouse gas emissions and particular climate change impacts.